Probe positioning and bonding device and probe bonding method

ABSTRACT

Disclosed herein are a probe positioning and bonding device and a probe bonding method, and more particularly a probe positioning and bonding device used to fix probes to prescribed positions on a substrate so that a probe card used for semiconductor integrated circuit testing equipment is manufactured, and a probe bonding method using the same. The probe positioning and bonding device comprises a stage unit disposed on a working table, a microscope disposed above the stage unit while being supported by means of a first supporting member disposed on the working table, a probe fixing unit disposed above the stage unit and below the microscope while being supported by means of a second supporting member disposed on the working table, and a light source unit supported by means of a third supporting member disposed on the working table. The light source unit is disposed toward the upper part of the stage unit.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a National Stage application under 35 U.S.C. §371 ofand claims the benefit of International Application No.PCT/KR2004/000560 filed on Mar. 16, 2004, which claims priority toKorean Application No. 10-2003-0016635, filed on Mar. 17, 2003, which ishereby incorporated by reference.

TECHNICAL FIELD

The present invention relates to a probe positioning and bonding deviceand a probe bonding method, and more particularly to a probe positioningand bonding device used to fix probes to prescribed positions on a probecard substrate, and a probe bonding method using the same.

BACKGROUND ART

Generally, semiconductor integrated circuit devices are tested whenmanufacturing the devices, after manufacturing the devices, or whenpackaging the devices, in order to verify whether the devices aremanufactured while the whole or partial electric characteristics of thedevices exactly correspond to the original design of the devices.

The equipment for performing the above-mentioned test is probe equipmentwith a test apparatus and a probe card. The probe card serves toelectrically connect a various electrical signals-generating part in thetest apparatus and a pad in the semiconductor integrated circuit device,or an electric signal detecting part in the test apparatus and the padin the semiconductor integrated circuit device.

One of the conventional probe cards is a needle-type probe card, whichis shown in FIG. 1 a. As shown in FIG. 1 b, the needle-type probe cardincludes needle-type probes 12 each having a bent end. The body of eachneedle-type probe 12 is disposed on a prescribed position of a ceramic13, and is then fixedly attached to the ceramic 13 by means of epoxy 14.The ceramic 13 is attached to a main circuit board 11. The other end ofthe needle-type probe 12 is connected to a prescribed circuit of themain circuit board 11 by means of soldering 15. In this way, theneedle-type probe card is prepared. However, the above-mentionedneedle-type probe card has a relatively large size or space.Consequently, the needle-type probe card is not suitable to testsmall-sized electronic elements, which are gradually miniaturizedaccording to the advancement of the technology. Furthermore, there iscreated interference between the adjacent needle-type probes whenneedle-type probes are densely disposed on the main circuit board. As aresult, there is generated noise when a high-frequency signal istransmitted, and thus an imprecise test is performed.

In order to overcome the above-mentioned drawback of the needle-typeprobe card, there has been developed a cantilever-type probe card. Asshown in FIG. 2 a, a bump 23 is formed on the surface of a substrate 22fixedly attached to a supporting member 21 by means of a connectionmember 24. To the end of the bump 23 is bonded one end of a supportingbeam 25 a. The supporting beam 25 a is provided at the other end thereofwith a probe tip 25 b.

The above-mentioned cantilever-type probe card is manufactured as shownin FIG. 2 b. On the surface of a silicon wafer 26 are formed thesupporting beam 25 a and the probe tip 25 b. On the surface of thesubstrate 22 is formed the bump 23, and epoxy 27 is applied to the upperend of the bump 23. Here, the probe tip 25 b and the supporting beam 25a are formed by means of photolithography and plating in order toprocess the silicon wafer 26. The bump 23 is formed on the surface ofthe substrate 22 by means of photolithography and plating in order toprocess the substrate 22. The epoxy 27 is applied to the upper end ofthe bump 23.

In the silicon wafer 26 and the substrate 22 manufacture as describedabove, one end of the supporting beam 25 a is connected to the upper endof the bump 23, and then the attached supporting beam and the bump areheated to a temperature of approximately 350° C. The supporting beam 25a is fixedly attached to the bump 23, as the epoxy 27 is molten.Subsequently, the silicon wafer is removed by means of etching.

However, the cantilever-type probe card manufactured as described abovehas the following drawbacks. First, it is difficult to verify with thenaked eye, from the outside, whether the probe tip 25 b is fixedlyattached to the supporting beam 25 a in the case that thephotolithography and plating method are applied to the silicon wafer 26.As a result, it can be verified whether the probe tip 25 b is fixedlyattached to the supporting beam 25 a only after the process of FIG. 2 cis finished. Consequently, defective probe cards may be produced inlarge quantities.

Second, the material of the substrate is mainly restricted to a ceramicmaterial since the heating is carried out at high temperature, i.e.,approximately 350° C., to fixedly attach the bump 23 of the siliconwafer 26 to the supporting beam 25 a of the substrate 22. Consequently,the unit production cost of the probe card is increased.

Third, there occurs heat expansion and heat contraction when thesubstrate 22 and the silicon wafer 26 are heated and cooled.Consequently, positional error is generated by difference ofhigh-temperature heat expansion at the attached parts due to differencesof heat expansion coefficients between the silicon wafer 26 and thesubstrate 22 made of the ceramic, and there occurs a shearing force dueto residual stress when the substrate and the silicon wafer are cooled,with the result that separation between the supporting beam 25 a and thebump 23 may be caused.

Finally, it is required that different kinds of photolithography beperformed on the basis of objects to be tested, which have variousarrangements (i.e., arrangements of pads on an element) when theabove-mentioned probe card is manufactured. Consequently, compatibilityof the probe card depending upon the change of the pad arrangements ispoor.

DISCLOSURE OF THE INVENTION

Therefore, the present invention has been made in view of the aboveproblems, and it is an object of the present invention to provide aprobe positioning and bonding device and a probe bonding method that arecapable of manufacturing a probe card at a normal temperature, usingvarious kinds of materials to reduce the cost of the probe card, andminimizing damage to probes due to generation of residual stress causedby heat expansion and heat contraction.

It is another object of the present invention to provide a probepositioning and bonding device and a probe bonding method that can beapplied even when pad arrangement of an object to be tested is changed.

In accordance with one aspect of the present invention, the above andother objects can be accomplished by the provision of a probepositioning and bonding device comprising: a stage unit disposed on aworking table; a microscope disposed above the stage unit while beingsupported by means of a first supporting member disposed on the workingtable; a probe fixing unit disposed above the stage unit and below themicroscope while being supported by means of a second supporting memberdisposed on the working table; and a light source unit supported bymeans of a third supporting member disposed on the working table, thelight source unit being disposed toward the upper part of the stageunit.

In accordance with another aspect of the present invention, there isprovided a probe bonding method comprising: a step 1 for disposing asubstrate having a bonding agent applied to a prescribed area thereof ona stage, and operating the stage to place a prescribed point of thesubstrate on the focal point of the microscope having the fixedposition; a step 2 for fixedly placing the probe on the focal point ofthe microscope to contact the probe to the prescribed point on thesubstrate; and a step 3 for emitting a laser beam to the connected partsof the prescribed point and the probe to bond the probe on thesubstrate, wherein a plurality of probes are bonded on the substrate bysuccessively repeating the steps 1 to 3 so that the probes having aprescribed arrangement are formed on the substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and other advantages of thepresent invention will be more clearly understood from the followingdetailed description taken in conjunction with the accompanyingdrawings, in which:

FIGS. 1 a and 1 b are a partial cross-sectional view and a plan viewrespectively showing an example of the conventional probe card;

FIG. 2 a is a cross-sectional view showing another example of theconventional probe card;

FIGS. 2 b and 2 c are cross-sectional views respectively illustratingthe manufacturing steps of the probe card shown in FIG. 2 a;

FIG. 3 is a perspective view showing a probe positioning and bondingdevice according to a preferred embodiment of the present invention;

FIGS. 4 a and 4 b are a perspective view and a front view, in section,showing a probe fixing unit of the probe positioning and boding deviceshown in FIG. 3; and

FIG. 5 is a flow chart illustrating a probe bonding method according toa preferred embodiment of the present invention.

BEST MODE FOR CARRYING OUT THE INVENTION

As shown in FIG. 3, a probe positioning and bonding device according tothe present invention comprises: a working table 100; a plurality ofsupporting members 101, 102, and 103 disposed on the working table 100;arranging members 104 and 105 connected to the supporting members 101and 103 and disposed horizontally; a stage unit 110 disposed at thecenter part on the working table 100; a microscope 120 attached to thearranging member 105 while the microscope is positioned above the stageunit 110, the microscope being supported by means of the supportingmember 103; a probe fixing unit 130 attached to the supporting member102 while being supported by means of the supporting member 102 suchthat one end of the probe fixing unit 130 is positioned at the centerpart of the upper surface of the stage unit 110; a light source unit 150attached to the arranging member 104 while being supported by means ofthe supporting member 101 such that the light source unit 150 isdirected to the center part of the upper end of the stage unit 110.

The working table 100 has a prescribed height from the floor so thatother parts of the probe positioning and boding device according to thepresent invention are disposed on the working table while being securelyfixed to the working table. The plurality of supporting members 101,102, and 103 are disposed at both ends of the working table 100 and atthe rear middle part of the working table 100, respectively. To theupper parts of the supporting members 101 and 103 are attached thearranging members 104 and 105 while being horizontally connected to eachother such that the microscope 120 and the light source unit 150 aredisposed on the arranging members, respectively.

The stage unit 110 is disposed at the center part of the upper surfaceof the working table 100. The stage unit comprises: an x-axis movingstage 111; a y-axis moving stage 113; a z-axis moving stage 115; and arotating stage 117, which are vertically disposed one on another frombottom to top. Each stage is provided with a control knob. Upon rotationof the control knobs, the rotating stage 117, which is disposed at theuppermost end of the stage unit, is placed on a working position, orseparated from the working position after each probe is bonded.

The microscope 120 is attached to one end of the arranging member 105such that the microscope is placed above the stage unit 110 while beingspaced a prescribed distance from the stage unit, as shown in FIG. 3. Anobjective lens is moved vertically by means of the microscope 120.Preferably, an eye lens of the microscope 120 has a cross line markedthereon to confirm the positions of the substrate and the probes so thatthe probes are arranged on the substrate or bonded to the substrate onthe basis of the cross line. The microscope 120 may be disposed at thefront middle part of the working table 100. In this case, the process ofbonding the probes can be observed from the above.

The probe fixing unit 130 is mounted to the side wall of the supportingmember 102, as shown in FIG. 3. One end of the probe fixing unit 130 isplaced at the center part of the rotating stage 117, which is theuppermost part of the stage unit 110. As shown in FIGS. 4 a and 4 b, theprobe fixing unit 130 comprises: a bracket 131 fixed to the supportingmember; a pincette 133 disposed inside the bracket 131; a reciprocatingmover 135 for operating the pincette 133; and an open angle controller137 for controlling an open angle of the pincette 133.

As shown in FIG. 4 b, the pincette 133 has a head part 133 a supportedby means of the bracket 131 by means of a fixed shaft member 139. On thefixed shaft member 139 is formed a thread. The head part 133 a of thepincette 133 is engaged with the thread of the fixed shaft member 139 bymeans of an adjusting member 141. Consequently, the pincette 133 can bemoved in the direction indicated by the arrow X upon rotation of theadjusting member 141.

At the lower ends of both side plates of the bracket 131 are disposedthe open angle controller 143 and the reciprocating mover 135,respectively, so that the open angle of gripping parts 133 b of thepincette 133 is controlled, as shown in FIG. 4 b. The left gripper ofthe gripping part 133 b of the pincette 133 is fixed by means of theopen angle controller 143. Furthermore, the open angle of the grippingparts is limited to a prescribed range by means of the open anglecontroller 143. The reciprocating mover 135 applies pressure to theright gripper of the gripping parts 133 b so that the distance betweenthe gripping parts 133 b is increased or decreased. As shown in FIG. 4a, the gripping parts 133 b of the pincette 133 have grooves H and H′formed at the insides of the lower ends thereof, respectively, so thatthe probe is easily gripped by means of the gripping parts.

The reciprocating mover 135 is a piston apparatus, which is operated bymeans of an air compressor C or electrically operated by means of asolenoid (not shown). The detailed construction of the reciprocatingmover will not be described. The operation of the reciprocating mover135 is carried out by means of a button switch S disposed at one sidethereof. An additional damper (not shown) may be mounted to control theoperating speed of the reciprocating mover 135.

The probe fixing unit 130 may be further provided with a stage (notshown) connected to the bracket such that the stage is vertically slidon the second supporting member. In this case, the probe fixing unit 130is moved upward without operation of the stage unit 110 so that a newprobe is gripped by means of the pincette 133 when each probe has beenbonded.

The light source unit 150 is movably disposed on the arranging member104. The light source unit 150 is provided with a laser source.Consequently, a laser beam is emitted through the lens so that a bondingoperation between the substrate and the probe is carried out by means ofthe generated heat.

The operation of the probe positioning and bonding device with theabove-stated construction according to the present invention is asfollows: Epoxy is applied to the surface of the probe card substrate sothat an epoxy layer is formed. After the stage unit 110 is lowered aprescribed distance, the substrate is placed on the upper surface of therotating stage 117 of the stage unit 110. The probe is inserted into thegrooves H and H′ of the pincette 133, and is then fixed to the pincetteupon operation of the switch S. Subsequently, the lower end of the probefixed to the pincette 133 is connected to a prescribed part of thesubstrate, to which the probe is to be bonded. In this course, themoving stages 111, 113, and 115, and the rotating stage 117 of the stageunit 110 are arranged at prescribed positions and in prescribeddirections. The light source unit 150 is operated so that the generatedlaser is emitted to the substrate, to which the probe is connected. Theepoxy on the surface of the substrate is molten by means of the emittedlaser. Consequently, the probe is bonded. The above-mentioned processesare repeatedly carried out for each probe. In this way, a probe card ismanufactured.

The above-mentioned probe bonding process will now be described in moredetail with reference to FIG. 5, which is a flow chart illustrating theprobe bonding method according to a preferred embodiment of the presentinvention.

Step 1 is a processing step carried out by means of the stage unit 110and the microscope 130. Specifically, step 1 is a step for disposing thesubstrate, to which the probes are bonded, on the stage unit 110 and forarranging and fixing the substrate on the stage unit 110 through afocusing operation on the substrate disposed on the stage unit 110 whileverifying the position of the substrate by means of the microscope 130(S101).

Step 2 is a step for unloading the stage unit 110, on which thesubstrate is fixed at the step 1, to a non-working position to provide aworking space for a probe feeding operation (S103).

Step 3 is a step for feeding the probe to the pincette 133 of the probefixing unit 130 using the space provided by means of the processingcarried out at step 2 so that the probe is fixed. Specifically, step 3comprises: a step for holding the probe with the pincette 133 of theprobe fixing unit 130 while the probe is maintained at a prescribedangle (S105); and a step for controlling the reciprocating mover 135 ofthe pincette 133 and the open angle controller 143 so that the tip endof the probe fixing by means of the probe fixing unit 130 is placed onthe cross line formed at the objective lens of the microscope 120 toarrange the probe (S107).

Step 4 comprises: a step for loading the stage unit 110, which isunloaded to the non-working position at step 2 to provide a workingspace for a probe feeding operation, to a home position where theoperation of the stage unit 110 is carried out (S109); and a step foradjusting the displacement and rotating angle of the stage unit 110loaded to the home position at the x and y plane on three-dimensionalcoordinates to accurately place the probe fixed by means of the pincette133 to the coordinates of the substrate, to which the probe is to bebonded (S111).

Step 5 is a step processed by means of the stage unit 110. Specifically,step 5 is a step for controlling the vertical displacement of the stageunit 110 to accurately position the stage unit to the substrate heightfor probe bonding (S113).

Step 6 is a step processed by means of the light source unit 150.Specifically, step 6 is a step for emitting a laser beam to theconnected parts of the substrate, which is accurately positioned at step5, and the probe, to bond the probe to the position to be bonded on thesubstrate (S115).

Step 7 is a step processed by means of the probe fixing unit 130.Specifically, step 7 is a step for stopping the supply of power, i.e.,electricity or air, to the reciprocating mover 135 to separate thebonded probe held by means of the pincette 133 from the probe fixingunit (S117).

Step 8 is a step for successively repeating the assembly steps carriedout at the steps 1 to 7 (S119 and S121). At step 8, it is verifiedwhether probes to be bonded or substrates to be bonded are left todetermine whether the assembly steps are to be repeatedly carried out ornot.

According to the probe bonding method as described above, a plurality ofprobes are assembled to a probe card by means of a bonding process,whereby the probe card is manufactured.

With the probe positioning and bonding device and the probe bondingmethod, it is not necessary to heat the whole substrate at hightemperature so that the probes are bonded, unlike the conventional art.Consequently, materials for the substrate are not restricted.Specifically, the material for the substrate is not restricted toceramic. For example, a synthetic resin may be used for the substrate.Also, it is not necessary to modify the bonding device or the bondingmethod even when the arrangement of the probes on the probe card ischanged. Consequently, the compatibility of the bonding device andmethod is distinguished. Furthermore, occurrence of errors caused duringthe probe bonding process is decreased since the probe bonding processis verified by means of the microscope.

INDUSTRIAL APPLICABILITY

As apparent from the above description, the present invention provides aprobe positioning and bonding device and a probe bonding method that arecapable of manufacturing a probe card at normal temperature, usingvarious kinds of materials to reduce the cost of the probe card, andminimizing damage to probes due to generation of residual stress causedby heat expansion and heat contraction.

Furthermore, the probe card can be easily manufactured even when padarrangement of pads of an element to be tested is changed.

Although the preferred embodiments of the present invention have beendisclosed for illustrative purposes, those skilled in the art willappreciate that various modifications, additions and substitutions arepossible, without departing from the scope and spirit of the inventionas disclosed in the accompanying claims.

1. An apparatus for positioning and bonding probes to a substrate of aprobe card, comprising: a stage unit on a working table, the stage unitbeing movable in three dimensions and supporting the substrate; amicroscope coupled to a first guide member positioned at a first portionof the working table and placed above the stage unit; a probe fixingunit mounting on a supporting member in such a configuration that theprobe fixing unit moves on the supporting member vertically to theworking table, an end portion of the probe fixing unit to which a probeis fixed being interposed between the microscope and the stage unit sothat the probe makes contact with the substrate at a connected portionthereof; and a light source unit movably coupled to a second guidemember positioned at a second portion of the working table, a laserbeing emitted to the connection portion of the substrate from the lightsource unit, to thereby bonding the probe to the substrate at theconnection portion of the substrate, wherein the probe fixing unitincludes: a bracket moveably secured to the supporting member andincluding a pair of plates and a shaft interposed between the plates; apincette moveably secured to the bracket and including a head portionsecured to the bracket and a gripping portion opposite to the headportion to which the probe is fixed, the head portion of the pincettebeing secured to the shaft in a space between the plates; and acontroller for controlling an open angle of the pincette, the controllerpositioned at a side of the pincette and applying a pressure to thepincette.
 2. The apparatus of claim 1, wherein the stage unit includesan x-axis moving stage, a y-axis moving stage and a z-axis moving stagemoving in an x-axis direction, a y-axis direction and a z-axis directionin a Cartesian coordinate system and a rotating stage rotated about thez-axis direction, and the x-axis moving stage, the y-axis moving stage,the z-axis moving stage and the rotating stage are vertically disposedone and another from bottom to top.
 3. The apparatus of claim 2, whereinthe substrate is positioned on the stage unit by three-dimensionalmovement of the stage unit in such a configuration that the connectedportion of the substrate corresponds to the probe gripped to the endportion of the probe fixing unit, and the position of the substrate isverified by the microscope.
 4. The apparatus of claim 1, wherein theprobe includes a supporting beam and a probe tip positioned on a firstend portion of the supporting beam, and the supporting beam of the probeis bonded to the connected portion of the substrate and the probe tipfaces outwards.
 5. The apparatus of claim 4, wherein the probe fixingunit moves vertically on the supporting member upward without movementof the stage unit, so that another probe is gripped by the probe fixingunit without change of the position of the substrate on the stage unit.6. The apparatus of claim 1, wherein the first guide member includes afirst supporting member fixed to the first portion of the working tableand a first arranging member extending from an end portion of the firstsupporting member in a first direction and the second guide memberincludes a second supporting member fixed to the second portion of theworking table and a second arranging member extending from an endportion of the second arranging member in a second direction opposite tothe first direction, and the microscope is coupled to the firstarranging member over the stage unit and the light source unit ismounted onto the second arranging member movably along the secondarranging member close to or away from the microscope unit.
 7. Theapparatus of claim 6, wherein the first and second guide members arepositioned at both sides of the stage unit on the working table and theprobe fixing unit supporting member is positioned on a backside of thestage unit on the working table.
 8. The apparatus of claim 1, whereinthe gripping portion of the pincette includes a pair of grooves facingeach other to which the probe is gripped.
 9. The apparatus of claim 1,wherein the bracket further includes an adjusting member installed tothe shaft and the head portion of the pincette is secured to theadjusting member in such a configuration that the pincette linearlymoves in accordance with a rotation of the adjusting member about theshaft.
 10. The apparatus of claim 1, wherein the controller includes anopen angle controller positioned at a first side of the bracket and areciprocating mover positioned at a second side opposite to first sideof the bracket the bracket, so that the opening angle of the grippingportion of the pincette is controlled by the pressure applied by thecontroller.
 11. The apparatus of claim 10, wherein the reciprocatingmover applies the pressure to the gripping portion of the pincette fromthe second side of the bracket while the open angle controller supportsthe gripping portion of the pincette at the first side of the bracket.12. The apparatus of claim 11, wherein the reciprocating mover appliesthe pressure to the gripping portion of the pincette by a pistonoperated by an air compressor or an electrical solenoid.